Noble metal surface degradation induced by organothiols

Copper, silver and gold layers evaporated on the muscovite mica (001) surface were exposed to a series of molecules containing an organothiol and/or a carboxylic acid chemical functional group to investigate the potential of these compounds to modify the surfaces. The surfaces were investigated using optical microscopy, atomic force microscopy, scanning electron microscopy, energy dispersive analysis of X-rays, and X-ray diffraction. Organothiols containing a carboxylic acid group were found to change the surface morphology drastically over a period of days, while molecules containing only one of these functional groups were usually not able to do so. The mechanism is most likely a reaction between the organothiol and the metal surface, forming a thermodynamically stable new compound. This finding could be of importance in the many applications where organothiols are used to functionalize noble metal surfaces

Organothiol monolayer formation directly on muscovite mica

Organothiol monolayers on metal substrates (Au, Ag, Cu) and their use in a wide variety of applications have been extensively studied. Here, the growth of layers of organothiols directly onto muscovite mica is demonstrated using a simple procedure. Atomic force microscopy, surface X-ray diffraction, and vibrational sum-frequency generation IR spectroscopy studies revealed that organothiols with various functional endgroups could be self-assembled into (water) stable and adaptable ultra-flat organothiol monolayers over homogenous areas as large as 1 cm . The strength of the mica-organothiol interactions could be tuned by exchanging the potassium surface ions for copper ions. Several of these organothiol monolayers were subsequently used as a template for calcite growth